bluetooth: Refactor Bluetooth and Stub out BluetoothInteraction.

Source/modules/bluetooth/BluetoothInteraction.idl

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// https://webbluetoothcg.github.io/web-bluetooth/#idl-def-bluetoothinteraction
+
+// Implement BluetoothInteraction interface: https://crbug.com/476985
+
+[
+    GarbageCollected,
+    NoInterfaceObject,
+    RuntimeEnabled=Bluetooth,
+] interface BluetoothInteraction {
+    // readonly    attribute BluetoothUUIDs uuids;
+    // Promise<BluetoothGATTService>        getService(DOMString serviceInstanceID);
+    // Promise<BluetoothGATTCharacteristic> getCharacteristic(DOMString characteristicInstanceID);
+    // Promise<BluetoothGATTDescriptor>     getDescriptor(DOMString descriptorInstanceID);
+};